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What Is A Telephone Hybrid? 1
1 What Is A Telephone Hybrid?
Telephone hybrids, or telephone balance units (TBUs) provide the interface
between professional audio equipment and the public telephone network.
They provide protection for your equipment and the public telephone
lines, allowing for varying line signals and line conditions. Automatically
cancelling out the unwanted signal they also facilitate two-way
communication down a single telephone line.
Each telephone hybrid has a telephone line connection, a handset
connection and separate terminals for audio input and output from a
broadcast mixer, or other professional audio source.
A large proportion of Sonifex hybrids are used in radio and television
broadcasting applications for allowing external callers to be connected
to the studio mixing console. Most of the other units are supplied to
communication operations for allowing extremely effective conversion
between 4-wire audio circuits and standard telephone lines.
The Best Telephone Hybrid in the World Just
Got Better!
The DHY-04 telephone hybrid is an enhanced redesign of the DHY-03, the
best performing telephone hybrid in the world. It now has auto-sensing
combined analogue and AES/EBU inputs and outputs, front panel Speed
Dial buttons, together with an Ethernet interface to allow web browser
access to the configuration and internal settings. All whilst still retaining
stunning line balance rejection figures. For the best sounding audio calls
you’re likely to hear, you should specify the DHY-04.
Key new features of the unit include:
• Auto-sensing combined analogue or AES/EBU XLR input.
• AES/EBU sample rates up to 24 bit/96kHz accepted.
• Configurable analogue or AES/EBU XLR output.
• Ethernet port for remote configuration via web browser GUI.
• Remote dialling and line hold control via Ethernet.
• DTMF dial tone recognition for reporter remote access - a journalist can
dial into the unit which can recognise a pre-programmed DTMF numeric
code to automatically connect the journalist on-air.
• Four front panel speed-dial buttons for dialling 7 internally phone Speed
Dial numbers.
• Front panel Redial button for redialling the last number.
Product Function:
Provides separation between send and receive signals on an analogue
telephone network, provides professional level balanced input & output
signals and has echo cancellation.
Typical Applications:
Radio & TV station talk shows, telephony interface to the mixer.
Features:
• Fully automatic - adapts to varying line conditions and has automatic
signal limiting.
• Fully adaptive echo cancellation to 250msec - default is 24msec.
• 70dB typical line balance rejection offering superb performance and
crystal clear audio.
• Front panel input and output gain controls.
• Front panel LED metering of receive and send signals.
• Built-in conferencing for 2 hybrids, so that a single telco channel on a
mixing desk can receive 2 calls.
• Integrated ring detector - automatic call answering after a pre-
determined number of rings.
• Automatic call disconnection. Fitted with K-break, line polarity reversal
and dial tone disconnect detection, defined by the country selection.
• Automatic ducking facility allows the talent to ‘shout-down’, or talk over,
a caller by reducing the gain of the caller’s signal if it goes above a certain
level.
